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Flexbox: center horizontally and vertically

How to center div horizontally, and vertically within the container using flexbox. In below example, I want each number below each other (in rows), which are centered horizontally.

.flex-container { padding: 0; margin: 0; list-style: none; display: flex; align-items: center; justify-content: center; } row { width: 100%; } .flex-item { background: tomato; padding: 5px; width: 200px; height: 150px; margin: 10px; line-height: 150px; color: white; font-weight: bold; font-size: 3em; text-align: center; }

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http://codepen.io/anon/pen/zLxBo

In your CSS you have row{ which has no effect on rows. If you change it to .row{ the result would be totally different.

M
Michael Gearon

I think you want something like the following.

html, body { height: 100%; } body { margin: 0; } .flex-container { height: 100%; padding: 0; margin: 0; display: flex; align-items: center; justify-content: center; } .row { width: auto; border: 1px solid blue; } .flex-item { background-color: tomato; padding: 5px; width: 20px; height: 20px; margin: 10px; line-height: 20px; color: white; font-weight: bold; font-size: 2em; text-align: center; }

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See demo at: http://jsfiddle.net/audetwebdesign/tFscL/

Your .flex-item elements should be block level (div instead of span) if you want the height and top/bottom padding to work properly.

Also, on .row, set the width to auto instead of 100%.

Your .flex-container properties are fine.

If you want the .row to be centered vertically in the view port, assign 100% height to html and body, and also zero out the body margins.

Note that .flex-container needs a height to see the vertical alignment effect, otherwise, the container computes the minimum height needed to enclose the content, which is less than the view port height in this example.

Footnote:
The flex-flow, flex-direction, flex-wrap properties could have made this design easier to implement. I think that the .row container is not needed unless you want to add some styling around the elements (background image, borders and so on).

A useful resource is: http://demo.agektmr.com/flexbox/


Flex items do not need to be block level unless the content they contain requires it. Also, you've prefixed all of the display properties, but didn't prefix any of the other Flexbox properties (which have different names in the other drafts).
@cimmanon I agree about with you about block level, and I edited my post accordingly. Block level is not required for alignment but may be needed if the user wants to specify height and so on. I took liberty about the browser prefixes, I just assumed a perfect browser for the sake of arriving at a working demo. Thank you again for your comment, appreciate the feedback.
If it overflows, it crops the top. i.imgur.com/3dgFfQK.png Any way to avoid this?
@BrianGates If the height of the window is too short, how do you want the 4 elements to be displays, 2x2, 1x4?
M
Michael Benjamin

How to Center Elements Vertically and Horizontally in Flexbox

Below are two general centering solutions.

One for vertically-aligned flex items (flex-direction: column) and the other for horizontally-aligned flex items (flex-direction: row).

In both cases the height of the centered divs can be variable, undefined, unknown, whatever. The height of the centered divs doesn't matter.

Here's the HTML for both:

<div id="container"><!-- flex container -->

    <div class="box" id="bluebox"><!-- flex item -->
        <p>DIV #1</p>
    </div>

    <div class="box" id="redbox"><!-- flex item -->
        <p>DIV #2</p>
    </div>

</div>

CSS (excluding decorative styles)

When flex items are stacked vertically:

#container {
    display: flex;           /* establish flex container */
    flex-direction: column;  /* make main axis vertical */
    justify-content: center; /* center items vertically, in this case */
    align-items: center;     /* center items horizontally, in this case */
    height: 300px;
}

.box {
    width: 300px;
    margin: 5px;
    text-align: center;     /* will center text in <p>, which is not a flex item */
}

https://i.stack.imgur.com/9Jbjt.png

DEMO

When flex items are stacked horizontally:

Adjust the flex-direction rule from the code above.

#container {
    display: flex;
    flex-direction: row;     /* make main axis horizontal (default setting) */
    justify-content: center; /* center items horizontally, in this case */
    align-items: center;     /* center items vertically, in this case */
    height: 300px;
}

https://i.stack.imgur.com/ccTOU.png

DEMO

Centering the content of the flex items

The scope of a flex formatting context is limited to a parent-child relationship. Descendants of a flex container beyond the children do not participate in flex layout and will ignore flex properties. Essentially, flex properties are not inheritable beyond the children.

Hence, you will always need to apply display: flex or display: inline-flex to a parent element in order to apply flex properties to the child.

In order to vertically and/or horizontally center text or other content contained in a flex item, make the item a (nested) flex container, and repeat the centering rules.

.box {
    display: flex;
    justify-content: center;
    align-items: center;        /* for single line flex container */
    align-content: center;      /* for multi-line flex container */
}

More details here: How to vertically align text inside a flexbox?

Alternatively, you can apply margin: auto to the content element of the flex item.

p { margin: auto; }

Learn about flex auto margins here: Methods for Aligning Flex Items (see box#56).

Centering multiple lines of flex items

When a flex container has multiple lines (due to wrapping) the align-content property will be necessary for cross-axis alignment.

From the spec:

8.4. Packing Flex Lines: the align-content property The align-content property aligns a flex container’s lines within the flex container when there is extra space in the cross-axis, similar to how justify-content aligns individual items within the main-axis. Note, this property has no effect on a single-line flex container.

More details here: How does flex-wrap work with align-self, align-items and align-content?

Browser support

Flexbox is supported by all major browsers, except IE < 10. Some recent browser versions, such as Safari 8 and IE10, require vendor prefixes. For a quick way to add prefixes use Autoprefixer. More details in this answer.

Centering solution for older browsers

For an alternative centering solution using CSS table and positioning properties see this answer: https://stackoverflow.com/a/31977476/3597276


can we do it horizontally right, left and vertically center?
@kapil, adjust the justify-content property to space-between or space-around... jsfiddle.net/8o29y7pd/105
This answer should be up on top. Using Flex should be the preferred way for doing this, since it scales nicely across devices and screen. Its far more easier than using floats and managing multiple divs adhere to that.
Ie 11 is not working properly horizontal and vertical center
thank you for noting that child elements are not automatically flex items. We need to cater to them if we want them to be.
b
ben

Add

.container {
    display: flex;
    justify-content: center;
    align-items: center;
}

to the container element of whatever you want to center. Documentation: justify-content and align-items.


P
Penny Liu

You can make use of

display: flex;
align-items: center;
justify-content: center;

on your parent component

https://i.stack.imgur.com/sBAyt.png


Q
QMaster

Don't forgot to use important browsers specific attributes:

align-items: center; -->

-webkit-box-align: center;
-moz-box-align: center;
-ms-flex-align: center;
-webkit-align-items: center;
align-items: center;

justify-content: center; -->

-webkit-box-pack: center;
-moz-box-pack: center;
-ms-flex-pack: center;
-webkit-justify-content: center;
justify-content: center;

You could read this two links for better understanding flex: http://css-tricks.com/almanac/properties/j/justify-content/ and http://ptb2.me/flexbox/

Good Luck.


this is a good point, for today (to support only the newest browsers) you just need the last two lines -webkit.. for safari and the last one for all the others
+1 because old 2009 and March 2012 working drafts still have significant user share (combined about 8% according to caniuse.com).
Flext doesn't work in safari, how could u solve that problem ?
I checked the last version of safari on windows many days ago and I don't remember it very well, but I'll check and will say you. Just please tell me what version of safari did you mean? and on which OS?
@user3378649 Latest safari version could support Flex-box, Please see this link: caniuse.com/#search=flexbox
M
MelanieP

1 - Set CSS on parent div to display: flex;

2 - Set CSS on parent div to flex-direction: column;
Note that this will make all content within that div line up top to bottom. This will work best if the parent div only contains the child and nothing else.

3 - Set CSS on parent div to justify-content: center;

Here is an example of what the CSS will look like:

.parentDivClass { display: flex; flex-direction: column; justify-content: center; }


k
kishore

Use this:

   html, body {
      display: flex;
      align-items: center;
      justify-content: center;
      height: 100%;
   }

for some HTML markup like this:

   <html>
      <body>
        <main>
          <button> abc </button>
          <p> something </p>
        </main>
      </body>
    </html>

html, body { display: flex; align-items: center; justify-content: center; height: 100%; }

something


P
Polar

diplay: flex; for it's container and margin:auto; for it's item works perfect.

NOTE: You have to setup the width and height to see the effect.

#container{ width: 100%; /*width needs to be setup*/ height: 150px; /*height needs to be setup*/ display: flex; } .item{ margin: auto; /*These will make the item in center*/ background-color: #CCC; }

CENTER


A
Aksana Tolstoguzova

margin: auto works "perfectly" with flexbox i.e. it allows to center item vertically and horizontally.

html, body { height: 100%; max-height: 100%; } .flex-container { display: flex; height: 100%; background-color: green; } .container { display: flex; margin: auto; } JS

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L
Leo

If you need to center a text in a link this will do the trick:

div { display: flex; width: 200px; height: 80px; background-color: yellow; } a { display: flex; align-items: center; justify-content: center; text-align: center; /* only important for multiple lines */ padding: 0 20px; background-color: silver; border: 2px solid blue; }


W
Wilson

https://i.stack.imgur.com/Q3n7s.png

CODE

HTML:

<div class="flex-container">
  <div class="rows">

    <div class="row">
      <span class="flex-item">1</span>
    </div>
    <div class="row">
      <span class="flex-item">2</span>
    </div>
    <div class="row">
      <span class="flex-item">3</span>
    </div>
    <div class="row">
      <span class="flex-item">4</span>
    </div>

  </div>  
</div>

CSS:

html, body {
  height: 100%;  
}

.flex-container {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100%;
}

.rows {
  display: flex;
  flex-direction: column;
}

where flex-container div is used to center vertically and horizontally your rows div, and rows div is used to group your "items" and ordering them in a column based one.


R
Rayees AC

You can add flex-direction:column to flex-container

.flex-container {
  flex-direction: column;
}

Add display:inline-block to flex-item

.flex-item {
 display: inline-block;
}

because you added width and height has no effect on this element since it has a display of inline. Try adding display:inline-block or display:block. Learn more about width and height.

Also add to row class( you are given row{} not taken as style)

.row{
  width:100%;
  margin:0 auto;
  text-align:center;
}

Working Demo in Row :

.flex-container { padding: 0; margin: 0; list-style: none; display: flex; align-items: center; justify-content:center; flex-direction:column; } .row{ width:100%; margin:0 auto; text-align:center; } .flex-item { background: tomato; padding: 5px; width: 200px; height: 150px; margin: 10px; line-height: 150px; color: white; font-weight: bold; font-size: 3em; text-align: center; display: inline-block; }

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Working Demo in Column :

.flex-container { padding: 0; margin: 0; width: 100%; list-style: none; display: flex; align-items: center; } .row { width: 100%; } .flex-item { background: tomato; padding: 5px; width: 200px; height: 150px; margin: 10px; line-height: 150px; color: white; font-weight: bold; font-size: 3em; text-align: center; display: inline-block; }

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R
Raghul SK

Hope this will help.

.flex-container {
  padding: 0;
  margin: 0;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: center;
}
row {
  width: 100%;
}
.flex-item {
  background: tomato;
  padding: 5px;
  width: 200px;
  height: 150px;
  margin: 10px;
  line-height: 150px;
  color: white;
  font-weight: bold;
  font-size: 3em;
  text-align: center;
}

While this code may answer the question, providing additional context regarding how and/or why it solves the problem would improve the answer's long-term value.
M
Marco Allori

Using CSS+

<div class="EXTENDER">
  <div class="PADDER-CENTER">
    <div contentEditable="true">Edit this text...</div>
  </div>
</div>

take a look HERE


since this is easily and widely supported by modern browsers with pure flexbox your library solution is surely not necessary. Especially since he asked how to do it using flex box not a css library.